Automatic controlling means for fractionating towers



A ril .19, 1949.

Filed May 9, 1946 R R. WHITLEY AUTOMATIC CONTROLLING MEANS FOR FRACTIONATING TOWERS 2 Sheets-Sheet l April 19, 1949- R. R. WHITLEY 5 AUTOMATIC CONTROLLING MEANS FOR FRACTIONATING TOWERS Filed May 9, 1946 2 -Sheets$heet 2 CON 7770!.

Patented Apr. 19, 1949 I AUTOMATIC CONTROLLING MEANS FOR FRACTIONATING TOWERS Record R. Whitley, Texas city Tex. Application May 9, 1946, Serial No. .csasss 1 Claim. (Cl. 202-160) This invention relates to automatic controlling means for a fractionating tower.

An object of the invention is to provide means of the character described whereby the heavier liquids may be relieved from the tower.

It is another object of the invention to provide means for automatically controlling the relief of said residual liquid resulting from the fractionating process. thereby controlling the specific gravity of the product.

A further object ofthe invention is to provide an automatic controlling equipment of the character described which will automatically regulate the relief of liquid from the tower irrespective of temperature variation.

With the above and other objects in view the invention has particular relation to certain novel features of construction, operation and arrangement of parts, an example of which is given in this specification ,and illustrated in the accompanying drawings, wherein- Figurev 1 is an enlarged, verticaLsectional view of an automatically operable, adjustable, flow controlling valve assembly employed; and,

Figure 2 is a fragmentary, vertical, sectional view of a fractionating tower equipped with the automatic controlling means.

Referring now more particularly to the drawings wherein like numerals of. reference designate the same parts in each of the figures, the numeral l designates a fractionating tower having the conventional transverse trays, or partitions, 2 therein. These partitions have the tubular upstanding nipples 3 which are partially enclosed above by the conventional bubble caps 4 and leading downwardly from the trays are the overflow conduits 5.

Between the upper and lower trays 2 there is a transverse partition 6 extending entirely across the tower l and forming a side stream draw, or stripping, tray. This partition has a central opening and surrounding this opening and upstanding therefrom there are the vapor tubes 1.

. 2 end of the stem I has the yoke I8 fixed thereon whose arms embrace an adjusting rod l'l, and'are pivoted thereto.

Mounted on the arm 10 there is a tubular fitting I8 into which the upper end of the rod l1 extends and mounted in this fitting there is a hand wheel shaft l9 whose upper end has a hand wheel 20 fixed thereon.

The lower end of the shaft I9 is threaded into an internally threaded socket extending axially into the rod H, as is illustrated in mycopendlng application for Adjustable level control filed December 22, 1945 under Serial No. 637,043, so that by turning the shaft Hi the rod H and the corresponding end of the stem 14 may be adjusted up and down.

There is a relief pipe 2| whose arms are anchored to and extend through the wall of the tower I. The free end of one of these arms is upwardly turned through the partition 6 and the free end of the other arm is downwardly. turned into the tray 2 beneath- Incorporated into the upper arm of this relief pipe there is a valve casing 22 which is connected'into the bottom of the arm l0 by means of a tube 23.

In the casing 22 there are the upper and lower valve seats. 24 and 25 through which the liquid .fiowing through the relief line 2| must pass.

On opposite sides of the tower I there are the I float chambers 8 and 9 which are of substantially similar construction. Extending laterally from the respective float chambers are the tubular arms [0 and II whose outer ends are closed.

I2 and I3 which are fixed to the inner ends of the respective float stems l4 and I5 which extend into the corresponding arms l0 and II. The outer These seats are controlled by the upper andlower disc valves 26 and 21 which are arranged'above the corresponding seats 24, 25 and which are fixed on a valve stem 28 within the tube 23 and whose upper end is connected to the float stem l4 between the float and the adjusting rod H.

The valve stem 28 extends beneath the lower seat 25 and fixed on said extended end there is a perforated disc 29 forming a stop to limit the upward movement of the valves.

The balanced valve mechanism above described has been provided to control the flow of reflux from the stripping tray 5 through the pipe 2| into the tray 2 beneath.

Should it be desired to change the level at which the liquid is to be maintained in the stripping tray 6 this may be readily done by adjusting the rod l1 and the corresponding end of the stem l4 upward or downward.

In order" to assure the true vertical movement The upper and lower ends of the float chambers 8 andii are connected into the fractionating tower I-, between the partition 6 and the bubble tray side of the diaphragm'52.

2 above by means of the respective upper and lower tubular nipples 3|, 32 and 33, 34 which are equipped with the shut-off valves 35, 35 and 31,

with the, shut-off valves 45 and 46 for drainage purposes.

Normally the valve 42 will be closed and the valves 39 and 40 open but if for any reason it should be desirable to bY-pass the balanced valve mechanism 22 the valves 39 and 40 maybe closed and the valve 42 open.

There is a discharge line 41 whose inner end extends inwardly through the wall of the fractionating tower and is sealed therewith and is upwardly turned and extends through the partition 6. This discharge line 41 is equipped with a balanced valve mechanism 48 similar to the mechanism of the valve 22 and which is operated by the valve stem 49 located in the tube 5|] and whose upper end is connected to the float stem I5.

The outer end of this float stem I5 is connected to an adjusting rod 5| similar to the rod I! but whose upper end is connected to a flexible diaphram 52 which spans the diaphram casing 53.

An airline 54 is connected, at one end, into the top of the casing 53 and, at its other end, it is connected into a conventional temperature control equipment 60. There is a thermo-couple 55 which is located in the fractionating tower chamher just beneath the partition 6, and this thermocouple is connected with the temperature control instrument 50 by the positive and negative conductors 6|, 62. The temperature control instrument has an air output from zero to fifteen pounds per square inch;

On opposite sides of the balanced valve mechanism 48 there are the shut-off valves 56, 51, incorporated into the line 41 and connected into the line 41 on opposite sides of the valves 56, 51 there is a by-pass pipe 58 incorporated into which there is a cut-ofi valve 59.

Normally the valves 56, 51 will be open and the valve 59 closed; however, if for any reason it should be desired to by-pass the balanced valve mechanism 48 this may be done by closing the valves 56, 51 and opening the valve 59.

The temperature controller is of such design that with a decrease in the temperature signal there will be an automatic decrease in the air output through the tube 54 against the upper Should there be a change in the distillation process that would cause a temperature decrease in the tower chamber beneath the partition 6, and should said decrease be below a point selected by the operator, the thermo-coupler 55 would be correspondingly affected and would in turn aiTect the temperature control instrument, through the conductors GI, 62 and should the decrease in temperature be out of harmony with the setting on the temperature control instrument the air output through the air line 54 would be decreased. This decrease in the air pressure will allow the compression spring 63 below the diaphragm 52 to upwardly also. The float l3, however, will remain in its same position. The float stem l5 will, therefore, be moved upwardly, thus lifting the valve stem 49 and opening the valve 48 to permit an increase in the flow of liquid from the stripping tray 6 through the distribution line 41 to a storage tank (not shown). The movement of liquid through the lines 41 and 34 will continue until the levels in the stripping tray 6 and within the housing 9 reach such a point as to cause the float I3 to be lowered; and, operating through the stems I5 and 49, will close the valve 48 and reduce the flow of 'liquid. The valve 48 will close before the stripping tray 6 has become empty.

At the same time, the level of the liquid in the chamber 8 will assume the same level as that in the chamber 9 and stripping tray 6, which level will be beneath that of the level before the temperature decrease. Therefore, upon downward movement of the float I2, the valve 22 will also be closed, thus reducing the cooling reflux .flow through the line 2| to the tray 2 below the stripping tray 6, thus causing the temperature in the chamber beneath the stripping tray 6 to rise to its original, the selected, temperature.

Should the temperature in the chamber beneath the stripping tray 6 rise, the automatic control instrument 60, under the influence of the thermo-couple 55, will increase the air pressure above the diaphragm 52, forcing it downwardly and closing the valve 48, thus resulting in a rise of the liquid level in the float chambers 8 and 9, and in the stripping tray 6. This action will cause the float l2 to rise and correspondingly open the valve 22, allowing an increase in flow of liquid through the line 2| into the tray 2 beneath and thus bringing the temperature within the chamber beneath the stripping tray back down to its selected point; thereupon the float l3 will take control and re-open the valve 48 so that the level of the liquid in the tray 6 will not become abnormal.

What I claim is:

Automatic controlling means for a fractionating tower having an upper stripping tray and a lower bubble tray therein, a reflux line leading from the stripping tray and discharging into the bubble tray beneath, a discharge line leading out of the stripping tray, float chambers on a common level, upper and lower tubular nipples connecting the upper and lower ends of the respective float chambers into the stripping tray, shut ofi valves controlling said nipples, a reflux valve controlling the flow of liquid through the reflux line, a discharge valve controlling the flow of liquid through the discharge line, manually adjustable means controlled by the level of the liquid in one of said chambers and controlling the reflux valve, means for controlling the discharge valve, said means being connected to the discharge'valve and including a float in the other chamber and also including a diaphragm adapted to be placed under fluid pressure to move the discharge valve toward closed position, a temperature controlling device responsive to the temperature inthe tower and efiective to apply said pressure upon an increase of the temperature, in the tower and to relieve said pressure upon a decrease of temperature in the tower and mechanicalmeans effective to move the discharge valve toward open position upon relief of said pressure.

7 RECORD R. WHI'I'LEY.

(References on following page) REFERENCES crmn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name I Date 1,229,189 Wingett June 5, 1917 1,614,877 Clapp Jan. 18, 1927 1,875,032 Landgraf at 9.1 Aug. 30, 1932 10 Number 

